Electricity isn't exactly a growth business, so Xcel Energy's employee head count doesn't budge much from year to year. One department is an exception: cybersecurity.
Xcel employs more than 100 highly trained security analysts, compared with a handful just two years ago. Threats from hackers are intensifying and, with them, the specter of blackouts.
"We have put considerable effort into it, and I think our cyber-defenses have gotten better. But the bad guys' cyber-offense has gotten better, too," said Ben Fowke, Xcel's CEO. "Our sophistication needs to improve."
Hackers last year broke into the IT systems of a Kansas nuclear power plant, though no damage was done. They have shut down parts of Ukraine's power grid twice in the last two years. And their attacks are becoming more refined.
"There has always been a constant stream of incidents," said Robert Lee, CEO of Dragos, a Maryland-based cybersecurity company. "What struck me this past year is the aggressiveness of hackers targeting infrastructure."
The nation's critical infrastructure ranges from oil pipelines to communications networks to the financial system, and at the heart of it all is the electricity grid.
"The reliability of the electricity system underpins virtually every sector of the modern U.S. economy," said the most recent Quadrennial Energy Review from the U.S. Department of Energy.
The report went on to say the U.S. grid is in "imminent danger from cyberattacks," and that such attacks could undermine much of the economy and the nation's "critical defense infrastructure."